We've seen law enforcement hold training sessions on what to do if there is an active shooter at your workplace, at a restaurant, or movie theater, but the Las Vegas massacre took place from high above an open venue, so how should we react in that situation?
At first, people thought they were hearing fireworks. But, the rapid rounds continued and reality set in when people started to see the wounded.
The first instinct for thousands was to get down. Palm Beach County Sheriff Ric Bradshaw said that's not always the best idea.
"The best response is to try to get something to get behind," said Sheriff Bradshaw. "Start getting behind the structures, get under the stage, I mean, find something somewhere that is a barrier between you and wherever you think this is coming from."
The mass shooting in Las Vegas is not only the deadliest in U.S. history, but it is very different from past shootings.
People were exposed in an outdoor venue and shots were coming from the 32nd floor of the Mandalay Bay Hotel.
"I heard one lady said she got under the bar. Perfect, right? It may not be the perfect place, but it's hard for a bullet to get through would versus just raining bullets down on you. So try to get something substantial that can get between you and wherever that is coming from. If that doesn't work, then run like heck," said Sheriff Bradshaw.
Bradshaw said playing dead can work as a last resort, but that strategy offers no protection.
He said this shooting stresses the importance of always knowing your escape routes even outdoors.
"If you’re here at the middle of the venue, is the quickest way out over here? Or is it straight ahead?" said Bradshaw.
Bradshaw said in cases where the shooter might be on the ground, then running long distances is a good idea to put distance between you and the person, but in this case taking cover is the best option because if you're running in an open-air venue then you're also exposed.